Highly porous materials have found widespread application in the manipulation of small molecules for gas storage, separating mixtures, catalysis, analysis, and detection. Among the many types of porous materials, metal-organic frameworks (MOFs) can provide exceptional characteristics or material properties. MOFs include porous crystals created from modular molecular “building blocks,” which can, in principle, be combined in an almost unlimited number of combinations. MOFs can provide exceptional characteristics or material properties, not only with regard to their relatively high surface area, porosity and stability, but also for the ease with which the MOFs can be synthesized based on designs conceived a priori. This latter benefit stems from the use of modular molecular “building blocks” that self-assemble into predictable crystal structures. Due to this predictability and the abundance of known modular building blocks, there have been reports of novel MOFs over the past few years and many in-depth investigations of their properties and functionality. While these reports showcase the success of the modular building block approach, they also belie the underlying combinatorial difficulty of finding the MOF with desired material properties for a given application, such as improved material properties or the best material properties for the application.
Our work shares much in spirit with at least one known database of hypothetical zeolites that was recently rapidly screened for gas adsorption properties. However, synthesis of such novel zeolites can be significantly more difficult than novel MOFs. For example, it is believed that less than 200 different zeolite structures have been synthesized to date, compared to thousands of MOFs over a much shorter time period.
As there are millions of possible MOFs even when considering libraries of fewer than one hundred building blocks, it can be difficult and time-consuming to find the MOF or MOFs having desired properties that are better than other MOFs or the best for a particular application.